With the increasing use of data processing and control systems, the problem of creating or querying a data base in such systems has become increasingly significant. Data is frequently entered into a system or queried from a system via a terminal having a keyboard.
Great strides have been made in the development of keyboards engineered to improve the performance of the data entry process and to facilitate the querying process by operators or users. For example, many data entry keyboards which contain a main array of keys, typically including alphabetic keys, also contain a separate numeric array for entering numeric input. The numeric array has been provided because it is well recognized that most operators can enter numeric data more rapidly with the use of a numeric array controllable by a single hand.
Many of the more sophisticated data processing or control systems require interaction between an operator or user and the system. Keyboards for such applications have frequently been enhanced with the addition of special purpose function keys. For example, keyboards using special function keys are used in terminals for document search systems for making searches of case and statutory law. When using such keyboards, an operator may use special function keys to cause the document search system to display part of a document in a special format, to display another document, or to print a display.
Another type of keyboard for which extensive use of function keys is desirable is the keyboard for the terminal used by telephone operators in operator assistance systems. A terminal for use in such a system is shown in The Bell System Technical Journal, Vol. 58, No. 6, Part 1, July - August 1979, p. 1258. In such systems, the operator must handle many specialized telephone control functions, such as allowing a person-to-person call to complete or collecting a coin deposit. A request to perform one of these specialized telephone operator functions is signaled most expeditiously to a control processor of the operator assistance system with the help of a special function key provided on the keyboard.
Telephone operators also enter predominantly numeric data into the operator assistance system using keys in a numeric array in conjunction with the operation of function keys. While there has been some attempt to place function keys in groups, no successful overall optimum grouping of the function keys and optimum placement of such groups with respect to the numeric array has been achieved. As a result, the actions of operators are slowed down by the need for conscious thought and excessive hand and wrist movement back and forth between the numeric array and the special function keys. This results in errors and an unnecessarily high expense for operator data entry and data query operations.